Assessment of WSe2 based BSF layer on CZTSSe solar cell using SCAPS-1D

CZTSSe is one of the emerging materials in the field of solar cell owing to large absorption coefficient, tunable bandgap, and relatively inexpensive production process. Around 12.6% efficiency has been reported for CZTSSe based solar cell in the literature. Surface recombination at the back contact of the solar cell has been considered to be an important limiting factor for the constrained values of efficiency. One of the possible ways to overcome this limitation is to introduce a back surface layer (BSF) in the cell. We in this paper report our results and analyze the same for possible adoption of the BSF layer of tungsten diselenide (WSe2) material in a CZTSSe based solar cell. The results show significant enhancement in open-circuit voltage (V
OC
), short-circuit current density (J
SC
) and fill factor (FF) due to introduction of BSF which increases its power conversion efficiency (PCE) from 12.57% to 17.20%. All the simulations in this research work are performed using SCAPS-1D simulator. Present research work may be an important step toward suggesting CZTSSe based solar cell structures with higher values of efficiency than currently being reported in the literature.